JPS6219926B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic clutch, and more particularly to an improvement in the magnetic circuit section of a clutch rotor containing an excitation coil.

Conventionally, a clutch rotor that constitutes an electromagnetic clutch is manufactured by hot-forging the rotor part 6' and pulley part 7', which constitute the magnetic circuit, from low-carbon steel and then going through a cutting process, as shown in Fig. 1. As shown in Fig. 2, the rotor part 6' and pulley part 7' which constitute the magnetic circuit are formed as separate parts and fixed together by welding or other joining means. Manufactured clutch rotors.

However, when forming the entire clutch rotor by cutting, it must be formed from a forged product with a large amount of excess material, which requires a large number of cutting processes and wastes a lot of material. was spending a lot of time on. Furthermore, as shown in FIG. 2, in the conventional press rotor 5', the area of the friction surface 6b' is small, so the frictional force between the friction surface 6b' and the suction plate 23' is small, and the suction holding force is reduced. In order to obtain a sufficient suction and holding force, the diameter of the clutch rotor 5' must be increased, which has the drawback of increasing the weight of the clutch rotor 5'. Furthermore, the rotor part 6' of the clutch rotor 5', which is manufactured by fixing together the rotor part 6' and the pulley part 7' which constitute a magnetic circuit, which are formed separately, has a cross-sectional shape as shown in FIG. A letter-shaped concentric double tube 6a' is formed, and the hatched portions 25' and 27' of the concentric double tube 6a' are cut to form a stepped portion 6e' and a stopper portion 13' of the ball bearing outer race.
As shown in FIG. 3b, a rotor part in which a step part 6e' and a stopper part 13' are formed by cutting a round bar material (not shown) and extruding the material by the forging method. It was hot.

However, the rotor portion 6' constituting the magnetic circuit formed by cutting as shown in FIG. 3a has the disadvantage that it requires a large number of machining steps and wastes a lot of material.

Furthermore, as shown in FIG. 3b, the rotor part 6' forming the magnetic circuit formed by extrusion cannot be tempered by work hardening, and accurate dimensions cannot be obtained when forming the stepped part 6e' and the stopper part 13'. Therefore, parts requiring precise dimensions had to be cut after extrusion.

In order to eliminate the above-mentioned drawbacks, the present invention provides a method for manufacturing a rotor part constituting a magnetic circuit of a clutch rotor, in which a step part of the rotor part is formed by drawing and ironing a plate-shaped material. It is also an object of the present invention to easily form a rotor portion constituting a magnetic circuit with good dimensional accuracy by simply cutting and pressing a stopper portion that holds the outer race of the bearing.

The present invention will be explained below with reference to drawings showing embodiments.

Reference numeral 1 denotes a main shaft that protrudes from inside the compressor body 2, and has a main shaft lead-out cylinder 3 that encloses the main shaft 1 and projects integrally from the compressor main body 2 on its outer periphery, and the outer circumferential surface of the main shaft lead-out cylinder 3 A clutch rotor 5 is rotatably fitted through a ball bearing 4 to the clutch rotor 5. The clutch rotor 5 has a rotor part 6 integrally forming a concentric double cylinder 6a and a friction surface 6b, and a pulley part 7 having a V-belt groove 7a for pulling a V-belt. A magnetic flux blocking slit 8 is formed on the friction surface 6b, and a stepped portion 6e is formed on the outer peripheral surface of the outer cylindrical portion 6c of the rotor portion 6.
Inside the clutch rotor 5, there is a substantially U-shaped section 12 in which a core 11 containing an excitation coil 10 is disposed.
form. Further, a stopper portion 13 of the outer race 4a of the ball bearing 4 is formed at the end of the inner cylindrical portion of the clutch rotor 5. At the rear end of the core 11 disposed in the substantially U-shaped cross section 12, the core 11 is fixed to the front surface of the compressor body 2 with a screw 14 so as to be concentric with other rotating parts. Fix the fixing plate 15 for this purpose.

At the outer end of the main shaft 1 protruding from the main shaft lead-out tube 3, a clutch hub 16 is attached with a half-moon key 17 and a fixing nut 18.
The clutch hub 16 has a washer 19, an inner end of the leaf spring 20, and a stop plate 21.
are caulked with the rivet 22 in this order, and the suction plate 23 facing the outer periphery of the clutch hub 16 with a gap is caulked with the rivet 54 on the outer end of the leaf spring 20, thereby tightening the clutch hub 16 and the clutch hub 16. The top plate 21 and the suction plate 23 are fixed concentrically.

The method of manufacturing the rotor portion 16 will be explained below with reference to FIG. 5. As shown in FIG. By forming the outer peripheral surface of the outer cylindrical portion 6c of the concentric double cylinder 6a into one piece and ironing and pressing the outer circumferential surface of the outer cylindrical portion 6c of the concentric double cylinder 6a as shown in b, the material of the shaded portion 25 is reduced and the material of the shaded portion 26 is increased to form a stepped portion. Form 6e. Further, as shown in c, the end of the inner cylindrical portion 6d of the concentric double tube is cut to form a protrusion 13a, and as shown in d, the protrusion 13a is press-worked to form a stopper portion 13 having an L-shaped cross section. form. Through the above four steps, the rotor part 6 configuring the magnetic circuit having the step part 6e and the stopper part 13 and having a substantially U-shaped cross section can be manufactured from the plate-shaped material.

As another example, a method of manufacturing the rotor part will be described below with reference to FIG. 6. As shown in FIG. When forming the outer cylindrical portion 6f, the inner circumferential surface 6g of the cylindrical portion having a diameter A is formed to be inclined, and as shown in b, the outer circumferential surface of the outer cylindrical portion 6f of the concentric double tube is ironed and pressed to form a diagonal line. The material of the portion 25 is decreased and the material of the shaded portion 26 is increased to form the step portion 6e to have the maximum diameter B. At the same time, the inclined inner circumferential surface 6g moves vertically to form an outer cylinder. The portion 6f is formed to have a diameter C of the inner peripheral surface 6g. At this time, by setting the diameters of each of the rotor parts 6 constituting the magnetic circuit to be B>A>C, ironing press work becomes easy, so that the step part 6e can be easily formed and has high dimensional accuracy. The subsequent formation of the stopper portion is carried out in the same manner as shown in FIGS. 5c and 5d, and the rotor portion 6 constituting the magnetic circuit is manufactured in the above-mentioned four steps.

As described above, in the present invention, the rotor portion 6 constituting the magnetic circuit of the clutch rotor 5 rotatably supported on the outer periphery of the ball bearing 4 is formed into a substantially U-shaped cross section by drawing and pressing a plate material. The concentric double tube 6a and the friction surface 6b are integrally formed, and the outer cylindrical portion 6c of the concentric double tube 6a is ironed and pressed to form a stepped portion 6e to maximize the area of the friction surface 6b. In addition, by forming the stopper part 13 having an L-shaped cross section by pressing the protrusion part 13a formed by cutting the inner cylindrical part 6d of the concentric double cylinder 6a, the conventional process requires a large amount of man-hours for the cutting process. The number of manufacturing steps for the rotor portion 6 constituting the magnetic circuit, which previously required time and effort, can be significantly reduced, and finishing can be made unnecessary since it can be easily and precisely machined by press working alone. Furthermore, since waste of material due to cutting can be eliminated, manufacturing costs can be significantly reduced.

Furthermore, since the stepped portion 6e can be formed only by press working, it is possible to increase the area of the friction surface 6b that contacts the suction plate 23, and when the same area of the friction surface as the conventional one is required, it is possible to increase the area of the friction surface 6b that contacts the suction plate 23. 6 can be made smaller in diameter, and the amount of plate-shaped material can be reduced, resulting in weight reduction. That is, it has an excellent effect that a small and lightweight rotor portion 6 with a large frictional area 6b can be obtained.

[Brief explanation of the drawing]

1 and 2 are vertical cross-sectional views showing a conventional example of an electromagnetic clutch, FIG. 3 is a manufacturing explanatory diagram of a rotor part constituting a conventional magnetic circuit, and FIG. 4 is an electromagnetic clutch showing an embodiment of the present invention. FIG. 5 is an explanatory diagram showing a method of manufacturing a rotor part constituting a magnetic circuit of the present invention, and FIG. 6 is an explanatory diagram showing another embodiment of a method of manufacturing a rotor part constituting a magnetic circuit. It is. 4...Ball bearing, 5...Clutch rotor,
6... Rotor part, 6a... Concentric double cylinder, 6b... Friction surface, 6c... Outer cylindrical part, 6d... Inner cylindrical part, 6e
...Step part, 10... Exciting coil, 11... Core, 12...
Approximately U-shaped cross section, 13...stopper part, 13a...
protrusion.

Claims (1)

[Scope of Claims] 1. In a rotor portion constituting a magnetic circuit of a clutch rotor having a substantially U-shaped cross section in which a core containing an excitation coil is disposed, the rotor portion is formed by pressing a plate-shaped material. The concentric double cylinder and the friction surface located at the end of the double cylinder and connecting the double cylinder are integrally formed, and the outer peripheral surface of the outer cylindrical part of the concentric double cylinder is iron pressed. A stepped portion protruding outward is formed on the outer periphery of the friction surface, a protrusion is formed by cutting the edge of the outer circumferential surface of the inner cylindrical portion, and the protrusion is pressed to bend radially inward. 1. A method of manufacturing a magnetic circuit section of an electromagnetic clutch, characterized in that the axial stopper section of a ball bearing that rotatably supports a clutch rotor is formed by processing.